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991.
Infection with influenza A(H1N1)pdm09 during the first wave of the 2009 pandemic: Evidence from a longitudinal seroepidemiologic study in Dhaka,Bangladesh
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992.
Troy D. Tuckey Mary C. Fabrizio Alicia J. Norris Mary Groves 《Marine and coastal fisheries : dynamics, management , and ecosystem science.》2017,9(1):564-572
Blue Catfish Ictalurus furcatus were purposefully introduced into freshwater tributaries to Chesapeake Bay in the past, and populations have subsequently spread to new areas, negatively impacting native communities and causing concern for resource managers. To aid development of management strategies, we implemented a multiyear (2012–2015) tagging study of invasive Blue Catfish in a 40-km stretch of the Potomac River to estimate survival and assess movement patterns. Blue Catfish (N = 1,237) were captured by electrofishing and double-tagged to allow us to estimate tag retention rates; we used reward tags to increase reporting rates. Recaptured fish (N = 104; 8.4% return rate) were at large for between 2 and 1,208 d. Tag retention rates were 0.88 (SE = 0.045) after 1 year and declined to 0.31 (SE = 0.107) after 2.7 years. The mean minimum distance moved by fish was 24.1 km (range = 0.0–112.6 km). Most (63%) fish displayed downriver movements, but distance moved was unrelated to fish size or days at large. Greater distances were observed among fish that moved downriver (34.4 km) than those that moved upriver (6.7 km). These results suggest high variability in movement behaviors for Blue Catfish inhabiting the tidal Potomac River from freshwater reaches to estuarine habitats. We estimated an annual apparent survival rate of 0.56 (SE = 0.057; Brownie tag-return model) across the study period. This survival rate is lower than survival rates reported from their native range. Long-distance movements of Blue Catfish in the Potomac River indicate that robust, large-scale control measures will be needed to reduce population abundance and minimize negative impacts of this species on native communities.
Received May 2, 2017; accepted September 12, 2017 相似文献
993.
994.
Adrian Gerald McNicholl Julio Ducons Jesús Barrio Luis Bujanda Montserrat Forné-Bardera Reyes Aparcero Julio Ponce Robin Rivera José María Dedeu-Cuso Pilar Garcia-Iglesias Miguel Montoro Alicia Bejerano Yolanda Ber-Nieto Belen Madrigal Eva Zapata Carmen Loras-Alastruey Manuel Castro Andrea Nevarez Javier P. Gisbert 《Gastroenterologia y hepatologia》2017,40(10):651-657
Background
Rapid Urease Test (RUT) is a simple, cheap and relatively fast method for diagnosing Helicobacter pylori infection. It is therefore the preferred method used for patients undergoing gastroscopy. Most kits require 24 h to give results. The new Ultra-Rapid Urease Test (URUT) kit by Biohit® requires less than 1 h.Objective
To determine URUT's diagnostic accuracy.Method
Prospective, blind, multi-centre study involving dyspeptic patients. One corpus biopsy and three antral biopsies were obtained during gastroscopy for standard histological analysis, RUT and URUT. The URUT result was checked after 1 min, 5 min, 30 min and 60 min and the RUT was checked over the course of 24 h. Histology was used as the gold standard test.Results
144 patients were included, 68% female, with a mean age of 49 years old; 50% were H. pylori positive. RUT and URUT diagnoses were correct in 85.9% and 90% of the cases, respectively. The mean waiting time for a positive RUT result was 6 h. The sensitivity, specificity, and positive and negative predictive values for RUT were, respectively, 82%, 90%, 89% and 84%. The URUT's results were similar (85%, 94%, 94% and 87%). These figures improved when patients taking PPIs were excluded (RUT: 86%, 91%, 93% and 83%; URUT: 91%, 94%, 96% and 89%). No statistically significant differences were found when comparing RUT and URUT distributions of correct diagnoses (McNemar's Test, p = 0.3) but there was a tendency towards better results with the URUT.Conclusion
The URUT is equivalent to (or slightly better than) the traditional RUT in diagnosing H. pylori infection, and provides results in less than an hour. 相似文献995.
Charlotte Warren-Gash Kate Childs Alicia Thornton Sanjay Bhagani Shirin Demma Ankur Srivastava Clifford Leen Kosh Agarwal Alison J. Rodger Caroline A. Sabin On behalf of the Joint UK CHIC liver transplant advisory group 《Infection》2017,45(2):215-220
This study assessed the likelihood of referral for liver transplantation assessment in a prospective cohort of patients co-infected with HIV and hepatitis B or C with complications of cirrhosis. There were 141 co-infected patients from 11 UK centres with at least one complication of cirrhosis recorded (either decompensation or hepatocellular carcinoma) out of 772 identified with cirrhosis and/or HCC. Only 23 of these 141 (16.3%) were referred for liver transplantation assessment, even though referral is recommended for co-infected patients after the first decompensation episode. 相似文献
996.
Identification of Novel HBV/HDV Entry Inhibitors by Pharmacophore- and QSAR-Guided Virtual Screening
Michael Kirstgen Simon Franz Müller Kira Alessandra Alicia Theresa Lowjaga Nora Goldmann Felix Lehmann Sami Alakurtti Jari Yli-Kauhaluoma Karl-Heinz Baringhaus Reimar Krieg Dieter Glebe Joachim Geyer 《Viruses》2021,13(8)
The hepatic bile acid transporter Na+/taurocholate co-transporting polypeptide (NTCP) was identified in 2012 as the high-affinity hepatic receptor for the hepatitis B and D viruses (HBV/HDV). Since then, this carrier has emerged as promising drug target for HBV/HDV virus entry inhibitors, but the synthetic peptide Hepcludex® of high molecular weight is the only approved HDV entry inhibitor so far. The present study aimed to identify small molecules as novel NTCP inhibitors with anti-viral activity. A ligand-based bioinformatic approach was used to generate and validate appropriate pharmacophore and QSAR (quantitative structure–activity relationship) models. Half-maximal inhibitory concentrations (IC50) for binding inhibition of the HBV/HDV-derived preS1 peptide (as surrogate parameter for virus binding to NTCP) were determined in NTCP-expressing HEK293 cells for 150 compounds of different chemical classes. IC50 values ranged from 2 µM up to >1000 µM. The generated pharmacophore and QSAR models were used for virtual screening of drug-like chemicals from the ZINC15 database (~11 million compounds). The 20 best-performing compounds were then experimentally tested for preS1-peptide binding inhibition in NTCP-HEK293 cells. Among them, four compounds were active and revealed experimental IC50 values for preS1-peptide binding inhibition of 9, 19, 20, and 35 µM, which were comparable to the QSAR-based predictions. All these compounds also significantly inhibited in vitro HDV infection of NTCP-HepG2 cells, without showing any cytotoxicity. The best-performing compound in all assays was ZINC000253533654. In conclusion, the present study demonstrates that virtual compound screening based on NTCP-specific pharmacophore and QSAR models can predict novel active hit compounds for the development of HBV/HDV entry inhibitors. 相似文献
997.
Laura Esquius Alicia Aguilar-Martínez Marina Bosque-Prous Helena Gonzlez-Casals Anna Bach-Faig Ester Colillas-Malet Gemma Salvador Albert Espelt 《Nutrients》2021,13(8)
Breakfast has a critical role in energy balance and dietary regulation. Consequently, it is considered an important component of a healthy diet, especially in adolescence, when there are great opportunities to consolidate habits and establish future patterns of healthiness in adulthood. Socioeconomic position (SEP) causes inequalities that are reflected in health behaviors, physical activity, mental health, and diet. Therefore, we conducted a cross-sectional study using data from the 2019–2020 DESKcohort project (Spain) to explore the relationships between breakfast and sociodemographic characteristics, health-related behaviors, and school performance of 7319 adolescents. Our findings showed that the prevalence of skipping breakfast every day was 19.4% in girls and 13.7% in boys and was related to students’ SEP. The risk of skipping breakfast was 30% higher in girls from the most disadvantaged SEP, in comparison to those in the most advanced SEP (prevalence ratio (PR) = 1.30; 95% confidence interval (CI) = 1.11–1.54). Also, boys from the most disadvantaged SEP showed 28% higher risk of skipping breakfast than those in the most advanced SEP (PR = 1.28; 95% CI = 1.04–1.59). In conclusion, future public policies should be adapted considering a SEP and gender perspective to avoid increasing nutritional and health inequalities. 相似文献
998.
999.
Ana María Martínez Paula Giudici Alicia Beatriz Trigub Raúl DElía Eduardo Heredia Rodrigo Ramelli Rubn Gonzlez Felipe Aza Ulises Gilabert 《Materials》2021,14(15)
Cd1−xZnxTe (0 ≤ x ≤ 0.1) ingots were obtained by Bridgman’s method using two different speeds in order to find the optimal conditions for single-crystalline growth. Crystalline quality was studied by chemical etching, the elemental composition by wavelength dispersive spectroscopy (WDS), tellurium (Te) precipitates/inclusions concentration by differential scanning calorimetry (DSC), optical transmission by Fourier transformed infrared spectrometry (FTIR), and band gap energy (Egap) by photoluminescence (PL). It was observed that the ingots grown at a lower speed were those of the best crystalline quality, having at most three grains of different crystallographic orientation. The average dislocations density in all of them were similar and correspond to materials of good quality. EPMA results indicated that the homogeneity in the composition was excellent in the ingots central part. The concentration of Te precipitates/inclusions in all ingots was below the instrument (DSC) detection limit, 0.25% wt/wt. In the case of wafers from Cd0.96Zn0.04Te and Cd0.90Zn0.10Te ingots, the optical transmission was better than that of commercial materials and varied between 60% and 70%, while for pure CdTe, the transmission range was between 50% and 55%, the latter being decreased by the presence of Te precipitates/inclusions. The band gap energy Eg of different wafers was experimentally obtained by PL measurements at 76 K. We observed that Eg increased with the Zn concentration of the wafers, following a linear regression comparable to those proposed in the literature, and consistent with the results obtained with other techniques. 相似文献
1000.
Adolescence is a developmental period characterized by neuronal remodeling and the maturation of adult emotionality, reproductive behavior and social behavior. We examined whether chronic cannabinoid exposure in adolescent rats alters female sexual motivation, estrous cyclicity, sucrose preference, and CB1R expression in adulthood. Female rats were administered with the synthetic cannabinoid agonist, CP-55,940 (0.4 mg/kg, intraperitoneal), daily during adolescent development (PND 35-45). In a subset of subjects, socio-sexual motivation was investigated in adulthood (PND 75-86) using a runway apparatus. Estrous cyclicity was tracked in adulthood via vaginal cytology and a single-mount test. A two-bottle sucrose preference test was also conducted to determine whether predicted changes in socio-sexual motivation might be linked to alterations in hedonic processing. CB1R expression was examined in two separate subsets of subjects, one sacrificed following drug treatment (PND 46) and one before behavioral testing (PND 74). Drug treatment significantly decreased adult preference for a male conspecific (sexual motivation), as assessed by both Run Time and Proximity Time, but did not affect estrous cyclicity or sucrose preference. CP-55,940 treatment also induced immediate, but transient, decreases in CB1R expression in the ventromedial nucleus of the hypothalamus and amygdala. Drug treatment did not affect CB1R expression in the nucleus accumbens (core or shell) or globus pallidus at either time point. We suggest that the endocannabinoid system may play a role in the maturation of neuroendocrine axes and adult female reproductive behavior, and that chronic exposure to cannabinoids during adolescence disrupts these neurodevelopmental processes. 相似文献